Field of the Application
The invention is directed to a substrate and a manufacturing method thereof, and more particularly, to a carrier substrate adapted to carrying components and a manufacturing method thereof
Description of Related Art
In general, copper pillars connecting with a package body and copper pillars connecting with a chip are formed on a conventional carrier substrate by performing an electroplating process twice. However, since a plurality of independent copper pillars are formed on a circuit layer exposed by a patterned dry film by electroplating through the patterned dry film as an electroplating mask, the copper pillars formed are easily prone to have a poor height uniformity or coplanarity therebetween due to process variation. As a result, in the subsequent, when the carrier substrate is electrically connected with the package body and/or the chip through the copper pillars, a joining reliability between the copper pillars and the package body or the chip is reduced easily.